On buses, cars and trucks of domestic production, internal combustion engines, electric, steam and gas turbine engines can be installed. The most widespread are piston internal combustion engines, i.e., those engines within which the fuel-air fuel mixture burns. The thermal energy released during this process is converted into mechanical energy by means of mechanisms and systems and, in the form of torque, is transmitted through the transmission to the drive wheels of the vehicle, setting it in motion. Such engines have sufficient power, relatively small size and weight, are compact, reliable, have a significant power reserve (for example, a passenger car can travel 450-500 km at one fuel tank), their manufacturing technology is well established,
What are the disadvantages of internal combustion engines?
The disadvantages of internal combustion engines include: difficult start in the cold season; increased noise emission of exhaust gases and their high toxicity, which adversely affects human health, animals and vegetation. Exhaust gases contain about 60 different substances, of which carbon monoxide, nitrogen oxides, aldehydes, sulfur dioxide and hydrogen sulfide are the most hazardous to human health. When working on leaded gasoline, the exhaust gases contain lead compounds that also negatively affect the human body.
How can I reduce exhaust emissions?Exhaust gas toxicity can be reduced by stratified combustion of the combustible mixture, timely and accurate adjustment of the carburetors to the lean fuel mixture, higher voltage supply to the spark plugs, for example, from a contact transistor or transistor ignition system, installation of carbon monoxide afterburners or filters that delay toxic substances. However, all of them are still expensive or complicated in design for mass application on production vehicles. Therefore, some of the cars that constantly operate in large cities (Moscow, Kiev, Tashkent, Tbilisi) are converted to gas fuel, which burns more fully in the engine cylinders and less toxic substances are released into the atmosphere.
What are the advantages and disadvantages of rotary piston engines?
In a rotary piston engine, the role of the piston is played by a rotating rotor, which allows you to abandon the crank and gas distribution mechanisms, therefore, reduce the size and weight of the engine at high power. The disadvantages of such an engine include: insufficient tightness of the rotor in the cylinder due to their increased wear, which requires the use of special heat-resistant materials; increased shaft rotation frequency (up to 10000 rpm); unstable idling; lack of efficiency and high toxicity of exhaust gases.
What are the advantages and disadvantages of gas turbine engines?The gas turbine engine also lacks crank and gas distribution mechanisms, but the high speed of the turbine shaft (up to 50,000 rpm) requires the installation of a reduction gear. In addition, the presence of a compressor, a heat exchanger and a combustion chamber made of special heat-resistant steel in it increases the cost of the engine. Fuel consumption in such an engine is slightly higher than that of a piston. Big noise exhaust. All this does not allow its use in cars, however, work on its improvement continues.
What are the advantages and disadvantages of steam engines?Steam engines are easy to maintain, unpretentious to fuel, since combustion is stable, they have high torque. The main disadvantage of such an engine is its low efficiency (not more than 20%), while it reaches 30 for a carbureted piston engine, and 40% for a diesel engine. In addition, steam engines are explosive (a steam boiler explodes) and are fire hazardous.
What reasons do not allow the use of electric motors in cars?Electric motors are reliable, silent, compact, easy to operate, easy to maintain. In fact, there are no drawbacks that inhibit the use of electric motors in cars. However, such an engine needs a powerful and reliable current source, but it is not yet available. Existing lead-acid batteries are too heavy, short-lived, and require frequent recharging. A car with such batteries has a power reserve of only 60-80 km. In addition, the limited reserves of lead, zinc, silver and other non-ferrous metals do not allow the transition to mass use of electric motors in cars.
Thus, the transition to new types of engines for automobiles is due to the solution of a number of technical and organizational issues that require large investments, replacement of technological equipment, and retraining of workers and engineering personnel. Therefore, the main engine in cars uses an internal combustion engine.